• 산업융합연구
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• 제20권10호
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• pp.209-218
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• 2022

마사지 치료는 1회 치료만으로 통증을 경감시키고 스트레스를 이완시킵니다. 그러나 아직까지 1회 마사지 치료의 효과에 대한 객관적인 데이터를 확인한 연구가 없었습니다. 그래서 본 연구에서는 마사지 치료와 동일한 효과가 있는 것으로 보고된 척추 마사지 기구로 1회 치료를 실시하여 통증 경감과 스트레스 이완의 효과의 증거를 확인하고자 하였습니다. 10년 전부터 시각적상사척도 4점의 요통이 있었던 45세 남자 환자 1인을 대상으로 척추 마사지 기구를 실시한 1차 실험과 침상안정을 실시한 2차 실험을 실시하였습니다. 시각적상사척도 측정과 실시간으로 심박 변이도를 측정하여 자율신경계를 확인하였고 총 5회 혈액검사를 실시하여 스트레스 관련 혈액검사(코르티솔, 에피네프린, 노르에피네프린)를 실시하였습니다. 침상안정을 취한 2차 실험에 비해 척추 마사지 기구로 1회 치료를 받은 1차 실험에서 유의미한 통증 감소효과를 보였습니다. 또한 1차 실험에서 자율신경계 활성도 및 부교감 신경계의 활성도가 증가되어 있었으며 혈중 에피네프린과 노르에피네프린이 감소되어 있었습니다. 이것은 기존의 마사지 치료 효과와 동일한 결과이며 1회 척추 마사지 기구를 통해 얻어지는 효과의 증거라 사료됩니다.

• 한국가스학회지
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• 제15권4호
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• pp.27-32
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• 2011

가스 설비의 증가와 함께 가스 사용시 안전관리가 중요해 지고 있다. 그 일환으로 국가적인 차원에서 U-safety 시스템 도입이 추진되고 있으며, 이를 위해서는 실시간으로 현장에서 가스 누출에 대한 검지가 가능해야 한다. 탄화수소류로 주로 구성된 가스의 누출 감지는 열저항을 이용하는 방식이지만, 도관에 함께 매설될 시에는 폭발 가능성으로 인해 적용이 불가하다. 이에 상온에서 메탄이나 일산화탄소와 같은 탄화수소류를 전기화학적 촉매 반응으로 검지할 수 있는 방법이 필요하다. 본 연구에서는 다공성 골드 분말을 팰렛 형태로 제조하여 백금 나노입자를 전해 도금법으로 도핑하여, CO의 $CO_2$ 산화 반응을 유도할 수 있는 촉매 전극을 제조하였다. Pt/PAu 전극의 경우, 약 21%의 CO 전환률을 보여서 탄화수소류의 상온 촉매전환과 함께 전기화학적 센싱이 가능함을 보였다. 이는 추후 메탄 가스 검지에 적용할 수 있는 여지를 마련했다고 판단된다.

• 공학교육연구
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• 제21권3호
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• pp.56-65
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• 2018

With rapid advance of technologies including information and communication technologies, jobs are evolving faster than ever. Architectural engineering is no exception in this regard, and the green architectural engineering is emerging fast as a promising new field. In this study, a Delphi study of expert architectural engineers are conducted to find out (1) near future prospects of the field, (2) near future emerging jobs, (3) competencies needed for these jobs, and (4) educational content necessary to build these competencies with regards to the green architectural engineering. Initial Delphi survey consisting of open-ended questions in the above four areas were conducted and came out with 65 items after duplicate removal and semantic refinements. Further refinements via second and third wave of Delphi results into 40 items that the 13 architectural engineering experts may largely agree upon as future prospects with regards to the green architectural engineering. Findings indicate that it is expected that the demand for green architectural engineering and needs for automatic energy control system increase. Also, collaborations with other fields is becoming more and more important in green architectural engineering. The professional work management skills such as knowledge convergence, problem solving, collaboration skills, and creativity linking components from various related areas seem to also be on the increasing need. Near future ready critical skills are found to be the building environment control techniques (thermal, light, sound, and air), the data processing techniques like data mining, energy monitoring, and the control and utilization of environmental analysis software. Experts also agree on new curriculum for green building architecture to be developed with more of converging subjects across disciplines for future ready professional skills and experiences. Major topics to be covered in the near future includes building environment studies, building energy management, energy reduction systems, indoor air quality, global environment and natural phenomena, and machinery and electrical facility. Architectural engineering community should be concerned with building up the competencies identified in this Delphi preparing for fast advancing future.

• 한국융합학회논문지
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• 제10권4호
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• pp.131-138
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• 2019

디젤엔진은 열효율이 높고 연비가 좋으며 CO, HC 및 $CO_2$의 배출량이 낮은 등 가솔린 엔진보다 상당한 장점이 있다. 그러나 디젤엔진은 배기가스 중에 $O_2$ 농도가 높기 때문에 NOx 저감이 어렵고, 삼원촉매를 적용하기 어렵다. Urea-SCR과 LNT는 디젤엔진에서 NOx를 연속적으로 저감하는데 활용 가능한 두 기술이다. 디자인 엔진에 Urea-SCR 시스템을 구현함으로써 2.5l 이상 엔진에서 Euro-6의 강화된 NOx 기준을 충족시킬 수 있게 되었다. 본 연구에서는 엔진 회전속도, 부하, 촉매 방식 및 $NH_3$/NOx 비율에 따른 NOx 저감 특성을 연구하여 NOx 저감을 극대화하는 조건을 제시하고자 한다. 또한 Euro-6 이상의 규제에 대응할 수 있도록 Urea-SCR에 대한 정밀한 실험 데이터를 제공하고자 한다.

• 해양환경안전학회지
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• 제25권6호
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• pp.780-787
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• 2019

본 연구에서는 국내외 저탄소 녹색성장을 위한 대안으로서 수소에너지와 그 이용 기술에 대한 관심이 높아지는 추세에 발맞춰 무탄소 연료인 수소를 LNG 의 주성분인 메탄, 메탄-프로판, 메탄-프로판-에탄 동축류 확산화염 내에 첨가하여 화염형상 및 연소생성물에 미치는 영향을 확인하였다. 상온상압 조건의 확산화염에 수소를 단계적으로 첨가하여 실제 생성되는 연소생성물의 변화 추이를 가스 분석기를 이용하여 실험적으로 관찰하였고 확산화염의 형상은 디지털카메라를 이용하여 단계적으로 관찰 하였다. 실험결과에서 확산화염에 수소를 첨가함에 따라 질소산화물의 생성량이 선형에 가깝게 증가하는 경향을 보였다. 이것은 수소의 상대적으로 높은 단열화염온도와 빠른 연소속도가 Thermal NOx의 생성을 촉진했기 때문이다. 반면 이산화탄소의 생성량은 감소하는 경향이 나타났는데 수소를 첨가함에 따라 메탄, 메탄-프로판, 메탄-에탄-프로판의 혼합 확산화염에 포함되어있는 전체 탄소비율이 줄어들어 이산화탄소의 생성량이 감소한 것이다. 이는 선박에서 LNG-수소의 혼합 연료사용으로 인해 온실가스인 이산화탄소를 저감할 수 있는 하나의 방안으로 고려될 수 있다는 것을 의미한다.

• 한국식품조리과학회지
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• 제31권1호
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• pp.33-40
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• 2015

For the globalization of Korean food restaurants, the kitchens should be equipped with proper ventilation systems and space to keep clean and ensure food safety. This study aimed to examine the ratio of kitchen to total space of restaurant and the suitability of the ventilation systems employed at Korean food restaurants. Data were collected by on-site survey of 12 Korean foods restaurants in Seoul. Length and width of the restaurants were measured with scale. Temperatures and air velocity around the heating equipment, working area, and hood were measured with a thermal imaging camera anemometer and thermometer. Statistical analyses were conducted with the SPSS program. The average space of the restaurants was $25.7m^2$. The ratio of kitchen to space was 0.22 for restaurants sized $32m^2$, 0.28 for $33-66m^2$, 0.21 for $66.1-99m^2$, 0.16 for $99.1-148.5m^2$, and 0.35 for those above $148.5m^2$. Average maximum and minimum air velocity around the hood were 0.28 m/sec and 0.22 m/sec, respectively. Under these conditions, the temperature of the working area was $41^{\circ}C$, presenting an uncomfortable indoor temperature for kitchen employees to work. When classifying 3 groups based on the minimum and maximum air velocity, the temperatures near the cooking area and in the hood of the restaurants showed significant differences among the three groups. When the maximum air velocity was over 0.3 m/sec, the temperature of the cooking area was as $30.1^{\circ}C$, showing a significantly lower temperature (p<0.01). Based on these results, the kitchen space rate of 0.25 to the total space and a ventilation system maintaining a maximum air velocity over 0.3 m/sec were recommended for ensuring the food safety of Korean foods restaurants sized 66 to $99m^2$.

• 한국의류산업학회지
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• 제4권3호
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• pp.248-253
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• 2002

The purpose of this study was to improve consumer sleeping life in quality and to suggest producers meet new consumer needs and demands, by examining the nationwide use of bedding, analyzing consumer sleeping life by category and age group, comparing the results with the findings of the nationwide studies by Sung Su-kwang (1992) and Lee Song ja (1995), and identifying the major trend of consumer sleeping life. Results and Discussion The findings of this study were as below: 1. The General Characteristics of the Subjects : Most of the housewives investigated were in their 30s and 40s, with 41.7% and 50.8% respectively. 2. Bedroom : When it comes to bedroom style, 47.8% put beds in their rooms with the Korean under-floor heating system, and 45.4% didn't place beds in their rooms with the same heating system. 3. The Purchase of Bedding : 49.0%, approximately half the homemakers, bought their current bed-clothes at bedding shops, and just 3.2% made them on their own at home. 4. The Use of Bedclothes : In summer, yam (flax, ramie fabric) and a single-layer bed sheet (41.9%) were in use most, followed by a single-layer quilt (34.5%). 5. Bedding Management The most common frequency of bedding disinfection by sunning was once a month (29.4%), followed by once per two weeks (23.9%) and once a week (19.0%) in the order named.

• KEPCO Journal on Electric Power and Energy
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• 제8권2호
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• pp.69-72
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• 2022

This paper actually investigates the load on major large-scale buildings in the downtown area, examines the economic feasibility of installing PV and ESS in a microgrid target building, and evaluates whether an electric vehicle capable of V2G through two buildings is effective as an economical analysis program (HOMER) was analyzed using. It is economical to install a mixture of ESS rather than using the whole PV, and it is shown that if there is an electric vehicle using the V2G function of EV, there is an economic effect to replace the PV. So that Incentives and policies are needed to replace a large area of PV and utilize the existing parking lot to lead EV as a resource of the microgrid. Currently, P2X technology that stores power as ESS or converts it to other energy to control when surplus renewable energy occurs in large-capacity solar power plants and wind farms, etc. This is being applied, and efforts are being made to maintain the stability of the system through the management of surplus power, such as replacing thermal energy through a heat pump. Due to the increase in electric vehicles, which were recognized only as a means of transportation, technologies for using electric vehicles are developing. Accordingly, existing gas stations do not only supply traditional chemical fuels, but electricity, and super stations that also produce electricity have appeared. Super Station is a new concept power plant that can produce and store electricity using solar power, ESS, V2G, and P2G. To take advantage of this, research on an urban microgrid that forms an independent system by tying a large building and several buildings together and supplies power through a super station around the microgrid is in full swing.

• 설비공학논문집
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• 제22권7호
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• pp.492-507
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• 2010

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2009. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of general thermal and fluid flow, fluid machinery and piping, and new and renewable energy. Various topics were covered in the field of general thermal and fluid flow such as an expander, a capillary tube, the flow of micro-channel water blocks, the friction and anti-wear characteristics of nano oils with mixtures of refrigerant oils, etc. Research issues mainly focused on the design of micro-pumps and fans, the heat resistance reliability of axial smoke exhaust fans, and hood systems in the field of fluid machinery and piping. Studies on ground water sources were executed concerning two well type geothermal heat pumps and multi-heat pumps in the field of new and renewable energy. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included the heat transfer in thermoelectric cooling systems, refrigerants, evaporators, dryers, desiccant rotors. In the area of industrial heat exchangers, researches on high temperature ceramic heat exchangers, plate heat exchangers, frosting on fins of heat exchangers were performed. (3) In the field of refrigeration, papers were presented on alternative refrigerants, system improvements, and the utilization of various energy sources. Refrigeration systems with alternative refrigerants such as hydrocarbons, mixed refrigerants, and $CO_2$ were studied. Efforts to improve the performance of refrigeration systems were made applying various ideas of suction line heat exchangers, subcooling bypass lines and gas injection systems. Studies on heat pump systems using unutilized energy sources such as river water, underground water, and waste heat were also reported. (4) Research trend in the field of mechanical building facilities has been found to be mainly focused on field applications rather than performance improvements. In the area of cogeneration systems, papers on energy and economic analysis, LCC analysis and cost estimating were reported. Studies on ventilation and heat recovery systems introduced the effect on fire and smoke control, and energy reduction. Papers on district cooling and heating systems dealt with design capacity evaluation, application plan and field application. Also, the maintenance and management of building service equipments were presented for HVAC systems. (5) In the field of architectural environment, various studies were carried to improve indoor air quality and to analyze the heat load characteristics of buildings by energy simulation. These studies helped to understand the physics related to building load characteristics and to improve the quality of architectural environment where human beings reside in.

• 한국가스학회지
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• 제22권6호
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• pp.76-89
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• 2018

지속적인 산업 발전에 따른 에너지 수급의 불안정 및 환경오염 문제가 대두됨에 따라 이에 대한 해결 방안의 일환으로 열병합발전 시스템의 보급이 활발해지고 있다. 국내의 경우 가스엔진을 이용한 열병합발전기의 안전성능에 대한 검사기준이 미비하므로 이에 대한 연구가 필요한 실정이다. 본 연구에서는 20 kW급 가스엔진 열병합발전 시스템에 적용 가능한 안전성능 관련 표준화 연구 수행을 위해 열병합발전 시스템의 국내 외 기준에 대한 안전성능 및 구조/재료 평가기준을 분석하였다. 또한, 위험요소 분석 및 HAZOP (Hazard and Operability Studies)을 이용한 위험성평가를 수행하여 가스엔진 열병합발전 시스템의 안전성능 평가(안)을 도출하였으며, 평가항목으로는 안전성능 관련 엔진 시동, 배관 기밀 성능, 살수 및 온도 상승 성능, 연소 성능, 전기 효율, 열효율, 종합 효율, 습도 성능 등이 포함된다. 가스엔진 열병합발전 시스템의 구조 및 재료와 관련하여 가스 및 수배관, 가스 조절 및 차단밸브, 금속 또는 비금속 재료의 내구성, 내열성, 내한성에 대한 평가항목을 도출하였다.